Kohl decides against '12 bid in blow to Dem efforts to keep Senate

Sen. Herb Kohl (D-WI), chairman of the Senate antitrust subcommittee, won't seek reelection in 2012.

Kohl, the quiet Wisconsin senator and owner of the NBA's Milwaukee Bucks, will depart from the Senate after four terms, setting up what could be a tough battle for his seat. Some immediate possible candidates could include former-Sen Russ Feingold (D), a liberal icon who has stayed politically active through his new Progressives United political action committee. Republicans might try to lure Rep. Paul Ryan (R), the House Budget Committee chairman who hails from a competitive district, to jump into the race.

Sen Kohl becomes the sixth senator in the Democrats' corner to decline reelection next year; Daniel Akaka (Hawaii), Jeff Bingaman (NM), Kent Conrad (ND) and Jim Webb (VA) have said they'll retire at the end of this term, as will Sen. Joe Lieberman (CT), an Independent who caucuses with Democrats. Democrats are defending 21 Senate seats next year, compared to 10 for Republicans. Democrats are also defending two seats held by Independents who caucus with Democrats.